ORGANIC CHEMISTRY REVISION QUESTIONS
3. Below is a list of some organic compounds
represented by the letters A to E.
1. (i) Explain the meaning of the
following terms used in organic
chemistry
(a) Hydrocarbon
(b) Functional group
(c) Isomerism
A
C
E
[3]
(ii) Draw the structural formula for the
following compounds
(a) Pentane
(b) 2,2-dimethylpropane
[2]
(iii) State that part that is responsible for
the following in any given organic
compound
(a) How the compound reacts
(b) Its physical properties
[2]
2. (a) State by giving reasons, the name of
each of the following organic
compounds.
(i)
(ii)
CH3CH2CH2CH3
CH3CH2CH3
[4]
(b) A to H are structural formulae of some
organic compounds.
CH4
C4H9OH D
CH3COOH
B
D
C4H10
C4H8
(a) Give the name of compound A
[1]
(b) Identify the two compounds, from the
list, that belong to the same
homologous series.
[2]
(c) (i) State the compound which has the
same functional group as ethanol
[1]
(ii) Draw the displayed molecular
structure of ethanol
[1]
(iii) Construct a chemical equation for
the hydration of ethane to form
ethanol
[1]
(d) (i) Give one compound that is an
unsaturated hydrocarbon, from the
list above.
[1]
(ii) Describe a chemical test for an
unsaturated hydrocarbon.
[1]
(e) Compound E is acidic.
(i)
State the name of the
compound E.
[1]
(ii)
Describe a test to show that
compound E is acidic.
[1]
4. The table below shows the structural
formulae of various monomers and the
polymers that can be made from them.
Give the letters which represent;
(i)
(ii)
Two organic compounds which
conform to the general molecular
formula CnH2n+2.
[2]
Two compounds which are not
hydrocarbons
[2]
(c) Explain why G and H are isomers
[1]
(d) B and D are members of the same
homologous series. Give a reason why
this statement is correct.
[1]
(e) Give the name of compound H.
[1]
(a) Identify the monomers which are
hydrocarbons.
[2]
(b) Name the monomer W.
[1]
(c) Draw the displayed structure for
polymer Y.
[1]
(d) (i) Identify the common feature among
the monomers in the table above. [1]
(ii) Give the name of the compound
with this feature.
[1]
(e) Decane, C10H22 can be cracked tp
produce hexane, C6H14 and butane,
C4H8. Explain the meaning of the word
cracking.
[1]
5. (a) Organic compounds form homologous
series. Give four characteristics of
members of any homologous series [4]
(b) (i) Draw the structure of an alkane with
two carbon atoms in the molecule [2]
(ii) Calculate the percentage by mass of
hydrogen in this alkane.
[2]
(ii)
(iii)
State the two types of cracking
Write down the two possible
products when the compound
C11H24 is cracked.
[4]
8. Plastics are organic polymers. The table
below describes two types of plastics.
Complete the table. Part of the table has
been completed for you as an example.
6. Organic acids are a homologous series of
compounds having the carboxylic group –
COOH joined to an alkyl radical.
(a) What is the general formula for organic
acids?
[1]
(b) Draw the structure of butanoic acid [1]
(c) A reaction between an alcohol and an
organic acid is described as
esterification and this is similar to
neutralisation.
(i)
Ehtylethanoate is an ester.
Name two reagent used to
prepare it.
[2]
(ii)
State two ways in which
esterification is different from
neutralisation.
[2]
(iii)
Write a balanced chemical
equation for the esterification
of ethylethanoate.
[2]
(d) Calculate the mass of ethylethanoate
formed from 15g of the organic acid. [2]
7. (a) The following compounds are members
of the homologous series of alkanes:
CH4, C2H6, C3H8, C4H10 and C5H12
(i)
(ii)
(iii)
State the formulae of the next two
members in this series
State with reason whether the
compound C9H18 belongs to the
family of alkanes or not.
Among the five members given,
state with reason the one with the
highest boiling point.
[6]
(b) The demand for petrol worldwide
increases every year. To meet the
demand, large molecules of
hydrocarbons are cracked.
(i)
What do you understand by the
term cracking?
[4]
9. Crude oil is an important raw material that
we need in modern life. Engineers process
and refine crude oil in a tower to produce a
number of fractions as shown in the
diagram below.
(a) Name the process used to separate the
fractions of crude oil.
[1]
(b) Name the two major elements that are
found in crude oil.
[2]
(c) State two differences in physical
properties between fractions extracted
at C and B.
[2]
(d) A large proportion of fraction A has the
molecular formula CH4. Write a
balanced chemical equation for the
complete combustion of the compound
with chemical formula CH4.
[2]
(e) Crude oil is a non-renewable energy
source. Explain what is meant by a nonrenewable source.
[1]
10. Protein
are
macromolecules.
naturally
occurring
(a) (i) Define the term macromolecule [1]
(ii) Name another naturally occurring
macromolecule.
[1]
(b) Proteins can be hydrolysed to amino
acids. State a suitable reagent and
condition for this hydrolysis.
[2]
(c) The structure of a section of a protein
can be represented as;
(a) Complete the table above.
[3]
(b) What is the best method of disposing of
polyvinylchloride and polymer B? [1]
(c) Name the products of protein
hydrolysis.
[1]
13. Study the following sequence of reactions.
Glucose → ethanol → ethene → polyethene
(i)
Describe one similarity in the
structure of a protein and the
structure of nylon.
[1]
(ii)
Describe one way in which the
structure of a protein differs
from the structure of nylon. [1]
(d) Protein and nylon are both made by
condensation polymerization. Explain
what is meant by condensation
polymerization.
[1]
11. Ethene, C2H4, is a hormone found in most
plants. Tomatoes release ethene as they
ripen. Fruit growers use ethane as a
ripening agent.
(a) Draw a displayed structural formula of
ethene.
[1]
(b) (i) State the homologous series to which
ethene belongs.
[1]
(ii) Give the general formula of this
homologous series.
[1]
(iii) State the molecular formulae of the
fourth and fifth members of this
homologous series respectively. [2]
(c) State one major source of ethene and
the method by which it is obtained. [2]
(d) Two of the substances made from
ethene are shown below;
(i) Name the substances R and S.
(ii) State one use of substance S
[2]
[1]
12. The table below shows some information
on two polymers.
(a) (i) What name is given to the process by
which glucose changes into ethanol?
[1]
(ii) Name the enzyme responsible for
the change in (i) above. What gas is
produced during this process? [2]
(b) Name the process and the catalyst used
when ethene changes into polyethene
[2]
(c) Draw the structure of polyethene with
three repeating units.
[1]
(d) When polyethene is burnt in excess air,
two products are formed. Name the
products.
[2]
(e) Polyethene is a non-biodegradable
substance. Explain what is meant by the
term non-biodegradable and state the
effect of such polymers on the
environment.
[2]
14. 4.2g of a gaseous hydrocarbon Z was
analysed and was found to contain 3.6g of
carbon and 0.6g of the other element.
(a) Using the information provided above,
deduce the molecular formula of the
hydrocarbon Z.
[4]
(b) Name the other element.
[1]
(c) Draw the molecular structure of
hydrocarbon Z.
[1]
(d) (i) To which homologous series does
hydrocarbon Z belong?
[1]
(ii) Write the general formula of the
homologous series to which
hydrocarbon Z belongs.
[1]
(e) The analysed hydrocarbon Z was later
burnt in limited supply of air although
such a reaction is dangerous.
(i)
Explain why the burning of
hydrocarbon
Z in limited
supply of air is dangerous. [2]
(ii)
Write the balanced chemical
equation for the burning of
hydrocarbon Z in limited supply
of air. Include state symbols. [2]
(f) Can hydrocarbon Z be polymerised?
Give a reason for your answer.
[2]
(g) Hydrocarbon Z was bubbled into
aqueous bromine and acidified
potassium manganite (VII). State what
was observed when ......
(i) hydrocarbon Z was bubbled into
aqueous bromine.
[1]
(ii) hydrocarbon Z was bubbled into
acidified potassium manganite (VII).
[1]
15. Carefully study the structural formula of an
organic compound below. The letters are
not the actual chemical symbols of the
respective elements.
(a) Name the chemical bond labelled Y [1]
(b) (i) Using the letters, write the
molecular/chemical formula of the
structure above.
[1]
(ii) How many elements are in this
compound?
[1]
(iii) Suggest two physical properties of
this compound.
[2]
16. Below is a sketch of a fractionating column
used in the fractional distillation of crude
oil.
[2]
(c) The molecules of the fractions lower on
the column do not have a lot of uses.
How can their use be enhanced?
[1]
17. Below are the chemical formulae of some
organic compounds.
CH3OH CH3COOCH3 CH4 CH3COOH C2H4
A
B
C
D
E
(a) Using the letter labels only, choose a
compound which;
(i) undergoes substitution reaction
(ii) is used in the making of perfumes
(iii) is used in the industrial
manufacture of ethanol
[3]
(b) (i) Describe a chemical test that is used
to distinguish compound D from
compound E.
(ii) State one use of compound C. [2]
(c) Part of the structure of terylene is
shown below.
(i) Draw the repeating unit in terylene
(ii) state one use of terylene
[2]
(d) Some people dispose of old and useless
terylene materials by burning them.
Explain the danger caused by this
method of disposal and suggest a better
way of getting rid of unwanted terylene
materials.
[3]
18. The series of processes below show the
links to the formation of an ester known as
ethyl ethanoate.
(a) State any one use for each of the
fractions A, B, C.
[3]
(b) Name and draw the structural formula
of the main constituent of natural gas.
(a) From the reaction scheme above, name
processes K, L and M.
[3]
(b) Construct the chemical equation
describing process K. Include state
symbols.
[2]
(c) State both the chemical name and
common name for substance P.
[2]
(d) State the general formula of the series
where substance P belongs.
[1]
(e) Give any two uses of ethyl ethanoate [2]
19. Propene (CH3 – CH = CH2) reacts with steam
to give a major product propan-2-ol.
(a) State the essential conditions in this
reaction.
[2]
(b) State the kind of reaction that occurs
between propene and steam.
[1]
(c) However, there is also a minor byproduct formed in such a reaction.
(i) Give the full (displayed) structural
formula and the systematic name of
this by-product.
[2]
(ii) How is the major product separated
from the minor product?
[1]
(d) State the general formula for alkenes
[1]
20. The following table shows some
information about the second member in
the respective homologous series.
Complete the table by filling in the correct
information.
[6]
21. Figure 21.1 below shows the structural
formula of an organic compound.
Figure 21.1
(a) (i) To which homologous series does
this compound belong?
[1]
(ii) Circle the functional group of the
homologous series to which the
compound belongs.
[1]
(b) (i) Name the organic product formed
methanol reacts with the organic
compound above.
[1]
(ii) To which homologous series does
this new compound belong?
[1]
(iii) State how the organic compound
formed in (b)(i) above can be
identified
[1]
22. (a) (i) What is meant by the term
unsaturated hydrocarbon?
[1]
(ii) Name one unsaturated hydrocarbon
and draw its structural formula. [2]
(iii) Name or write the chemical formula
of the product formed when
bromine and the named unsaturated
hydrocarbon combine.
[1]
(iv) Name one saturated hydrocarbon
and draw its structural formula. [2]
(b) (i) Which one of the two named
hydrocarbons in (a)(ii) and (iv) can be
converted to a polymer?
[1]
(ii) Name the polymer and draw its
structure.
[2]
(iii) State one environmental
disadvantage of the polymer named
in (b)(i).
[1]
23. Pentane is a member of a homologous
series of organic compounds.
(a) Define the phrase homologous series
[1]
(b) Give any two characteristics of a
homologous series, illustrating your
answer with a suitable example.
[4]
(c) Pentane is an example of a compound
that exhibits isomerism.
(i) What do you understand by isomers?
(ii) Draw and name the structures of any
two isomers of pentane.
[5]
(d) Chloroethene is a monomer that can be
used to form an addition polymer.
(i) What is meant by the term
monomer?
[1]
(ii) Draw the structure of the monomer
chloroethene.
[1]
(iii) Name the polymer formed from
chloroethene.
[1]
(iv) Give two important uses of the
polymer formed from chloroethene
[2]
(v) Give one disadvantage of plastics
[1]
24. Ethene,
C2H4
is
an
unsaturated
hydrocarbon. It is manufactured from
petroleum as shown in the flow diagram.
(a) Name the two processes Y and Z.
[2]
(b) Describe either process X or Z,
include necessary conditions for any
reactions.
[2]
(c) Ethene can undergo hydrogenation
process with hydrogen. Write the
reaction equation using displayed
structures.
[2]
25. Both fats and proteins are natural polymers.
(a) Name the synthetic polymer that has
the same linkage as:
(i) fats
(ii) proteins
[2]
(b) (i) Draw the type of linkage found in the
synthetic polymer named in (a)(i)
above and name the linkage.
[2]
(ii) Synthetic polymers are nonbiodegradable. What is meant by
this statement?
[1]
(c) The structure displayed below is for
another natural polymer.
(i) Name this polymer
[1]
(ii) Is this polymer an addition or a
condensation polymer? Give a
reason for your answer.
[2]
(iii) Draw the structure of the monomer
used to synthesize this polymer. [1]
(iv) What type of linkage is found in this
polymer?
[1]
26. Ethanol, C2H5OH, can be manufactured by
two different processes.
 Process 1 – the catalyzed addition
of steam to ethane
 Process 2 – the fermentation of
glucose
(a) Name the type of reaction used to
manufacture ethane.
[1]
(b) (i) Write the equation for process 1.
(ii) Suggest the name of the alcohol
made when the alkene C3H6 reacts
with steam in the presence of a
catalyst.
[2]
(c) The equation for process 2 is shown
below.
C6H12O6(aq) → 2C2H5OH(aq) + 2CO2(g)
(i) Describe two essential conditions
required for efficient fermentation.
[2]
(ii) Suggest one advantage of
manufacturing ethanol by process 2
rather than by process 1.
[1]
(d) Process 2 makes an aqueous solution
of ethanol. Suggest a method of
purification that can be used to
remove water from the aqueous
ethanol.
[1]
(e) Describe a chemical test which could
be used to positively identify the
carbon dioxide formed during
fermentation.
[2]
(f) Other than process 1 and 2, suggest
another reaction from which ethanol
might be produced.
[1]
27. The diagram below gives a summary of the
breakdown of starch to maltose and then to
ethanol.
(a) Name the process represented by the
letters A and B.
[2]
(b) What is the purpose of the yeast in
process A?
[1]
(c) Apart from water, which other product
is produced when a mixture of propanol
and
concentrated
potassium
dichromate is heated?
[1]
(d) If ethanol is added to the product in
part (c) in the presence of concentrated
sulphuric acid;
(i) name the class of compounds to
which the product belongs.
[1]
(ii) give one everyday use of the product
in (i) above.
[1]
28. Plastics are made of macromolecules called
polymers. In the middle of the Pacific Ocean
there is a huge area of water that is
contaminated with small bits of plastics.
The water plastics have washed away from
the coastline.
(a) Part of the structure of one of the
polymers found in the ocean is shown
below.
(i) Name this type of polymer [1]
(ii) Draw the structure of the
monomer used in the
manufacture of this polymer [1]
(iii) Explain why this polymer is
described as a saturated
hydrocarbon.
[1]
(b) Suggest why this polymer is not
destroyed in water.
(a) Name the other product formed in this
reaction.
[1]
(b) Draw the structures of the compounds
in the boxes below:
(c) Suggest one commercial use for propyl
ethanoate.
[1]
(a) The Table gives the boiling points of
some alkanes.
(i)
(ii)
(iii)
Ethane
Propane
Butane
Pentane
C2H6
C3H8
C4H10
C5H12
(ii)
Boiling
point (°C)
- 88
- 42
0
36
Identify two characteristics of
a homologous series shown in
the table above.
[2]
Plot a graph of boiling points
against number of carbon
atoms for the alkane in the
table.
[3]
Use your graph to deduce the
boiling point of hexane.
[1]
(b) A hydrocarbon has the formula C8H16.
Explain why this is not an alkane. [1]
(c) In some parts of the world, butane is
used as a fuel for room heaters. If
What causes incomplete
combustion?
Construct an equation to show
that incomplete combustion of
butane produces carbon
monoxide and water only. [2]
31. Propane and
compounds.
propene
are
organic
(a) State one similarity and one difference
between the structures of propane and
propene
[2]
(b) Name a substance that can be used to
distinguish between propane and
propene. In each case, describe what
you would see.
[3]
(c) Another compound, Z, can be
polymerized to form polystyrene. Part
of the structure of polystyrene is
shown below;
(i)
(ii)
30. The question is about alkanes.
Formula
(i)
[1]
29. Propanol, C3H7OH, reacts with ethanoic
acid, CH3COOH, to form ester propyl
ethanoate.
Name
these are faulty, incomplete
combustion occurs and carbon
monoxide is produced.
(iii)
Draw the structure of
compound Z.
Name the two products which
are formed by complete
combustion of polystyrene
Give one advantage of
disposing of waste polystyrene
by burning.
[4]